The present invention relates to novel, end-functionalized, linear, non-crosslinked polyolefins without pendant chain branched groups, and to a process for the preparation of these end-functionalized, linear, non-crosslinked polyolefins without pendant chain branched groups. This process is improved over other known processes in that it utilizes a chain transfer agent free of protecting groups, and hence forms the end-functionalized, linear, non-crosslinked polyolefins directly, without the need of further purification or deprotection after polymerization.
Hydroxyl-end functionalized polybutadienes synthesized via Ring Opening Metathesis Polymerization (or ROMP) are disclosed in Chung et. al. (U.S. Pat. No. 5,247,023), Grubbs, et. al. (U.S. Pat. No. 5,750,815) and Nubel, et al (U.S. Pat. Nos. 5,512,635, 5,559,190, 5,519,101 and 5,403,904). However, these polybutadienes are synthesized in a 2-step process where the first step involves polymerization and the second step involves conversion of the polymer chain ends to hydroxyl functionality.
The use of transition metal complexes to catalyze metathesis reactions with functionalized olefins is well known. U.S. Pat. Nos. 6,048,993, 6,111,121, 5,917,071, 5,831,108, 5,710,298, 5,342,909 and 5,312,940 describe the synthesis of various metathesis catalysts useful for this purpose. U.S. Pat. Nos. 5,880,231, 5,849,851, 5,750,815, 5,728,917 and 5,559,190 describe processes by which these catalysts are used to make functionalized polymers. U.S. Pat. Nos. 6,060,570, 5,731,383, 5,880,231 and 5,990,340 describe processes for making end-functionalized linear non-crosslinked polyolefins without chain branched groups where the cyclic olefin (1,5-cyclooctadiene) and a functionalized chain transfer agent (1,4-diacetoxy-2-butene) were used for the synthesis of linear end-functionalized materials. The use of a difunctional chain transfer agent such as 1,4-diacetoxy-2-butene creates hydroxyl end-functionalized polybutadienes having a functionality of 2.0. In these examples, however, after polymerization, the chain ends must be converted into hydroxyl functionality to form the end-functionalized polyolefin.
The present invention relates to the use of a chain transfer agent that is designed to ensure efficient reaction with traditional metathesis catalysts and 1,5-cyclooctadiene but forms a hydroxyl end-functionalized polybutadiene directly, without the need for further purification of the polymer. U.S. Pat. No. 5,360,863 describes the synthesis of these CTAs and the subsequent incorporation of these materials in coating compositions.
Polyurethane elastomers made from these hydroxyl end-functionalized polybutadienes have been described previously (U.S. Pat. No. 5,589,543 and Cell Polym 1996, 15(6), 395). As described therein, hydroxyl end-functionalized polybutadiene was reacted with diisocyanates and extended with chain extenders to produce polyurethanes. In one example of using the one-shot procedure, molten diphenyl-methyl diisocyanate (MDI) and butane diol are blended with the hydroxyl end-functionalized polybutadiene and the reaction mixture is compressed under elevated temperature and pressure to form the polyurethane. In another example, toluene diisocyanate (TDI) and the hydroxyl end-functionalized polybutadiene are reacted to form a prepolymer, and the resultant prepolymer was chain extended with methylene-bis-ortho chloroaridine (MbOCA). The mixture is then compressed under elevated temperature and pressure to form a polyurethane. The polyurethanes formed under these conditions had improved hydrolytic stability and reasonable mechanical properties. U.S. Pat. No. 5,990,340 also describes prepolymers made with hydroxyl end-functionalized polybutadiene and various diisocyanates.
Co-pending U.S. application Ser. No. 09/140,208 filed on Aug. 26, 1998, now U.S. Pat. No. 6,166,166which is commonly assigned, relates to a process for preparing thermoplastic polyurethane materials. This process comprises a) casting an NCO-terminated prepolymer with 1,4-butanediol to form a casting composition, b) extruding the casting composition to form a polyurethane elastomer, c) pelleting the polyurethane elastomer to form pellets, and d) processing the pellets to form a thermoplastic material. Suitable NCO-terminated prepolymers comprise the reaction product of a polyisocyanate with an end-functionalized, linear, non-crosslinked polyolefin without pendant chain-branched groups which is prepared by reacting 1,4-diacetoxy-2-butene with 1,5-cyclooctadiene in the presence of a ruthenium complex catalyst.
The processes known and described in the art relate to the synthesis of hydroxyl end-functionalized polybutadienes and require large quantities of organic solvents such as, for example, tetrahydrofuran (or similar solvent) to saponify acetate end-groups into hydroxyl functionality. Additionally, large quantities of methanol (or similar non-solvents) must be used in the polymer purification. These solvents increase both production costs and disposal costs. Tetrahydrofuran is a hazardous material, and thus, its use and treatment is expensive and environmentally unacceptable. Accordingly, it is desirable to develop a process for the production of hydroxyl end-functionalized, linear, non-crosslinked, polyolefins without pendant chain branched groups that does not require enormous quantities of these organic solvents.
In general, improvements in the production of hydroxyl end group functionalized polyolefins have focused on the catalysts used in the polymerization. It is the object of the present invention, however, to provide a process for the synthesis and purification of hydroxyl end-functionalized, linear, non-crosslinked, polyolefins without pendant chain branched groups through improvements to the chain transfer agent, and, thereby eliminating the need for purification or further processing after polymerization.
This invention relates to a novel, end-functionalized, linear, non-crosslinked polyolefin that is free of pendant chain branched groups, and to a process for the preparation of these end-functionalized, linear, non-crosslinked polyolefins that are free of pendant chain branched groups.
As used herein, the terminology xe2x80x9cfree from pendant chain branched groupsxe2x80x9d describes a polymer where no pendant chain branched group(s) is (are) created during the process of making the polymer. Polymerization of monomers or chain transfer agents containing pendant side chains such as phenyl rings, pendant functionality, alkyl chains, etc, which therefore create pendant chain branched groups in the resultant polymers are, however, considered to be within the scope of the present application. In other words, polymers having pendant chain branched groups which correspond to the pendant chain branched groups of the monomers used to prepare the polymers are within the scope of the present application. For example: the polymerization of 4-methylpentene creates a polymer which contains a pendant methyl group attached to every 5th carbon atom. Since this methyl group was present in the starting monomer, the resultant polymer is considered to be within the scope of the present invention.
The end-functionalized, linear, non-crosslinked polyolefin without pendant chain branched groups comprise the reaction product of: (A) a cyclic olefin monomer, with (B) a chain transfer agent comprising the reaction product of an unsaturated dihydric alcohol and an alkylene oxide, in the presence of (C) a catalyst, wherein the functionality of the polyolefin as defined by vapor phase osmometry (VPO) and end group titration ranges from 1.7 to 2.2, and the polyolefin has a structure corresponding to: 
wherein:
R1: represents a hydrogen atom or an alkyl group, preferably an alkyl group having 1 to 6 carbon atoms;
R2: represents a hydrogen atom or an alkyl group, preferably an alkyl group having 1 to 6 carbon atoms;
m: represents an integer from 0 to 1,000, preferably from 0 to 5;
p: represents an integer from 0 to 1,000, preferably from 0 to 5; and
n: represents an integer from 3 to 1,000, preferably from 3 to 200;
wherein:
the sum of p+mxe2x89xa71.
The present invention also relates to a process for the preparation of an end-functionalized, linear, non-crosslinked polyolefin without pendant chain branched groups comprising:
(l) polymerizing via ring opening metathesis:
(A) a cyclic olefin monomer (preferably 1,4-cyclooctadiene); with
(B) a chain transfer agent having the structure: 
xe2x80x83wherein:
R1: represents a hydrogen atom or an alkyl group, preferably an alkyl group having from 1 to 6 carbon atoms;
R2: represents a hydrogen atom or an alkyl group, preferably an alkyl group having from 1 to 6 carbon atoms;
m: represents an integer from 0 to 1,000, preferably from 0 to 5;
p: represents an integer from 0 to 1,000, preferably from 0 to 5; and
n: represents an integer from 1 to 1,000, preferably 1;
wherein:
the sum of p+mxe2x89xa71;
said chain transfer agent being the reaction product of:
(1) at least one unsaturated diol (preferably 2-butene-1,4-diol); and
(2) at least one alkylene oxide (preferably propylene oxide);
wherein components (1) and (2) are present in relative molar ratios of about 1:1 to 1:1000, preferably 1:2 to 1:4, and most preferably of about 1:2; in the presence of
(C) a catalyst (preferably a ruthenium metal carbene catalyst).
The resultant linear, non-crosslinked polyolefin is free of chain branched groups, except of course for those arising directly from the structure of the CTA or the monomer, and is characterized by a functionality of from 1.7 to 2.2, preferably from 1.95 to 2.05, and most preferably of about 2.0.
Suitable chain transfer agents for the present invention include but are not limited to, for example, those known and described in, for example, U.S. Pat. No. 5,360,863, the disclosure of which is herein incorporated by reference. These chain transfer agents correspond to the general structure: 
wherein:
R1: represents a hydrogen atom or an alkyl group, preferably an alkyl group having from 1 to 6 carbon atoms;
R2: represents a hydrogen atom or an alkyl group, preferably an alkyl group having from 1 to 6 carbon atoms;
m: represents an integer from 0 to 1,000, preferably from 0 to 5;
p: represents an integer from 0 to 1,000, preferably from 0 to 5;
n: represents an integer from 1 to 1,000, preferably 1;
wherein:
the sum of p+mxe2x89xa71.
These chain transfer agents comprise the reaction product of:
(1) at least one unsaturated diol (preferably 2-butene-1,4-diol); and
(2) at least one alkylene oxide (preferably propylene oxide);
wherein components (1) and (2) are present in relative molar ratios of about 1:1 to 1:1000, preferably of about 1:2 to 1:4, and most preferably of about 1:2.
Suitable chain transfer agents for the present invention include those corresponding to the general structure: 
wherein:
R1: represents a hydrogen atom or an alkyl group, preferably an alkyl group having from 1 to 6 carbon atoms;
R2: represents a hydrogen atom or an alkyl group, preferably an alkyl group having from 1 to 6 carbon atoms;
m: represents an integer from 0 to 1,000, preferably from 0 to 5;
p: represents an integer from 0 to 1,000, preferably from 0 to 5;
n: represents an integer from 1 to 1,000, preferably 1;
wherein:
the sum of m+pxe2x89xa71.
These chain transfer agents comprise the reaction product of:
(1) at least one unsaturated diol (preferably 2-butene-1,4-diol); and
(2) at least one alkylene oxide (preferably propylene oxide); wherein components (1) and (2) are present in relative molar ratios of about 1:1 to 1 :1,000, preferably of about 1:2 to 1:4, and most preferably of about 1:2.
The end functionalized linear non-crosslinked polyolefins of the present invention are characterized as being free of pendant branched groups. These polyolefins are preferably polybutadienes, but other examples include polyethylene, polypropylene, polystyrene, poly(4-methylpentene), polynorbornene, poly(oxanonorbornene), etc. Polyolefins of the present invention have functionalities in the range of from 1.7 to 2.2, preferably about 2.0, as defined by vapor phase osmometry (VPO) and end group titration. VPO is generally measured by ASTM D3592.
The end-functionalized, linear, non-crosslinked polyolefins without pendant chain branched groups of the present invention correspond to the general structure: 
wherein:
R1: represents a hydrogen atom or an alkyl group, preferably an alkyl group having 1 to 6 carbon atoms;
R2: represents a hydrogen atom or an alkyl group, preferably an alkyl group having 1 to 6 carbon atoms;
m: represents an integer from 0 to 1,000, preferably from 0 to 5;
p: represents an integer from 0 to 1,000, preferably from 0 to 5; and
n: represents an integer from 3 to 1,000, preferably from 3 to 200;
wherein:
the sum of p+mxe2x89xa71.
These polyolefins comprise the reaction product of:
(A) a cyclic olefin monomer, with
(B) a chain transfer agent, in the presence of
(C) a catalyst.
In general, any cyclic olefin containing from about 4 to about 30 carbon atoms can be utilized in the presence of a functionalized olefin to prepare the olefinic compounds of this invention. The cyclic olefins include both mono- and polycyclic unsaturated hydrocarbon compounds. Representative examples of suitable polycyclic unsaturated hydrocarbon compounds include norbornene, norbornadiene, 2,2,2-bicyclooctene-2, dicyclopentadiene and the like.
The preferred unsaturated alicyclic compounds are those compounds which comprise a single unsaturated alicyclic ring. These alicyclic rings may be mono- or multi-substituted by such groups as alkyl, aryl, arylalkyl, and halogen groups.
Representative examples of unsaturated alicyclic compounds containing a single alicyclic ring having at least 4 and not more than 6 carbon atoms, preferably having 4 or 5 carbon atoms in the cyclic ring and containing one double bond in the ring, are cyclobutene, cyclopentene, and cyclohexene.
Representative examples of unsaturated alicyclic compounds containing at least six carbon atoms, preferably at least seven carbon atoms, in the cyclic ring and containing one or more (preferably more than one) non-conjugated carbon-to-carbon double bonds in the cyclic ring include cyclooctene; 1,4-cyclohexadiene; 1,4- and 1,5-cyclooctadiene;
1,4,7-cyclononatriene, cyclodecene, cyclododecene, 1,4-, 1,5- and 1,6-cyclodecadiene: 1,4-, 1,5-, 1,6- and 1,7-cyclododecadiene; 1,4,7- and 1,5,9-cyclododecatriene and the like.
The most preferred unsaturated alicyclic compounds of this invention are those containing from one to three carbon-to-carbon double bonds in the ring and in which the double bonds are located in relation to each other in a manner that they are not adjacent and are non-conjugated. Representative examples of such preferred materials are cyclobutene, cyclopentene, cyclooctene, cyclododecene, and 1,5-cyclooctadiene, 1,5,9-cyclododecatriene and 1,9,17-cyclotetracosatriene.
Representative examples of substituted alicyclic compounds are alkyl-substituted compounds such as 1-methyl-1,5-cyclooctadiene; aryl-substituted compounds such as 3-phenyl-1-cyclooctene: aralkyl-substituted compounds such as 3-benzyl-1-cyclooctene; alkaryl-substituted compounds such as 3-tolyl-1-cyclooctene and halogen-substituted compounds such as a 5-chloro-1-cyclooctene, 1-chloro-1,5-cyclooctadiene; 5-chloro-1-cyclododecene and 5,6-dichloro-1-cyclooctene. Mixtures of the unsaturated alicyclic compounds are suitable, including both substituted unsaturated alicyclic compounds and the unsubstituted unsaturated alicyclic compounds.
Suitable chain transfer agents for the present invention include those which correspond to the general structure: 
wherein:
R1: represents a hydrogen atom or an alkyl group, preferably an alkyl group having from 1 to 6 carbon atoms;
R2: represents a hydrogen atom or an alkyl group, preferably an alkyl group having from 1 to 6 carbon atoms;
m: represents an integer from 0 to 1,000, preferably from 0 to 5;
p: represents an integer from 0 to 1,000, preferably from 0 to 5; and
n: represents an integer from 1 to 1,000, preferably 1;
wherein:
the sum of m+pxe2x89xa71.
These chain transfer agents comprise the reaction product of:
(1) at least one unsaturated diol as described above; and
(2) at least one alkylene oxide as described above;
wherein components (1) and (2) are present in relative molar ratios of about 1:1 to 1:1000, preferably of about 1:2 to about 1:4, and most preferably of about 1:2.
Examples of suitable chain transfer agents include compounds such as, for example, the reaction product of 2-butene-1,4-diol and ethylene oxide, the reaction product of 2-butene-1,4-diol and propylene oxide, the reaction product of 2-butene-1,4-diol with propylene oxide followed by the reaction with ethylene oxide in a sequential order (or vice versa), the reaction product of 2-butene-1,4-diol with a mixture of propylene oxide and ethylene oxide simultaneously, etc. A preferred chain transfer agent comprises the reaction product of 2-butene-1,4-diol and propylene oxide. Suitable chain transfer agents for the present invention can be prepared by the process described in, for example, U.S. Pat. No. 5,360,863, the disclosure of which is herein incorporated by reference.
Suitable unsaturated diols for component (1) above include alcohols such as, for example, dihydric alcohols having from 4 to 10 carbon atoms, preferably from 4 to 6 carbon atoms. Some examples of suitable dihydric alcohols include 2-butene-1,4-diol, etc. and mixtures of such compounds. The preferred chain transfer agent for the present invention is based on 2-butene-1,4-diol.
Suitable alkylene oxides for component (2) of the present invention include, for example, alkylene oxides having from 2 to 8 carbon atoms (preferably 3 to 6 carbon atoms), and having 1 epoxy group. Some examples of such compounds include ethylene oxide, propylene oxide, butylene oxide, styrene oxide, etc. and mixtures thereof. Propylene oxide is preferred.
The relative molar ratios of unsaturated diol(s) to alkylene oxide(s) are from about 1:1 to about 1:1000, preferably from about 1:2 to about 1:4, and most preferably of about 1:2.
The process for the preparation of an end-functionalized linear non-crosslinked polyolefin without pendant chain branched groups comprises:
(l) polymerizing via ring opening metathesis
(A) a cyclic olefin monomer as described hereinabove; with
(B) a chain transfer agent as described hereinabove, in the presence of
(C) a catalyst (preferably a ruthenium metal carbene catalyst).
Suitable catalysts for the present invention include, for example, those as described in and prepared according to the process disclosed in, for example, U.S. Pat. No. 5,342,909, the disclosure of which is herein incorporated by reference. Other metathesis catalysts include transition metal catalysts such as those containing ruthenium, osmium, titanium, tungsten, and the like. Similar types of catalysts which are useful in the present invention also include those described in U.S. Pat. Nos. 5,142,190, 5,198,511, 5,296,566, 5,559,190, and 5,312,940, as well as U.S. Pat. No. 5,342,909, the disclosures of which are herein incorporated by reference. In a preferred embodiment of the present invention, the catalyst comprises a ruthenium metal carbene complex based compound. Most preferably, the catalyst comprises bis(tricyclohexylphosphine) benzylidene-ruthenium dichloride.
It is of course, also possible that additives are present in the process of the present invention. Suitable additives include, for example, antioxidants or other stabilizers such as, for example, light stabilizers or heat stabilizers, plasticizers, lubricants, etc.
The ring opening metathesis polymerization process (i.e., ROMP) which is used in the presently claimed process to prepare the end-functionalized polyolefins is known and described in the prior art. See, for example, U.S. Pat. No. 5,880,231, the disclosure of which is herein incorporated by reference.
The end-functionalized linear non-crosslinked polyolefins without pendant chain branched groups of the present invention can be used, for in example, as a new polymeric diol containing no ester or ether bonds which could be incorporated into various polyurethane applications and the like, to improve hydrophobicity, acid and base resistance, impact properties in current polymer formulations, etc. HFPB""s may also find applications in polyurethane applications such as thermoplastic urethanes (TPU""s), thin films, fibers, cast elastomers and the like.